NEC NEAX NDA-24349 - Manual (Page 352)

Chapter 16 Wireless System
Page 16-14 NEAX2000 IPS Request for Proposal (RFP) Reference Guide
NDA-24349, Issue 4
Zone Transceiver II (ZT)
Access to the communications network by the D term PS III user is gained through radio connection with
one of the several Zone Transceivers installed on the premise. ZTs are placed strategically around the
establishment in an overlapping fashion to provide continuous radio coverage throughout the specified
area. The number of Zone Transceivers needed to provide service for any single establishment is
defined by several factors:
ƒ The total area requiring wireless service, which is a function of the area of operation of the users of the
D term PS III handset. Even in the case of providing a small number of handsets, if staff whose job requires
wireless service throughout the whole facility uses them, the number of ZTs is determined by the size of
the facility, not the number of users.
ƒ The configuration, environment and construction of the building(s) in the areas requiring coverage have
considerable impact on the effective coverage area of any one Zone Transceiver. Spacing of ZTs is
adjusted according to these conditions resulting in considerably different quantities needed to cover equal
amounts of square footage when compared from site to site.
ƒ Special conditions, such as coverage inside elevators and stairwells (both are typically not covered). In
addition, accommodating high traffic areas will result in additional Zone Transceivers. Typical
deployments provide access to at least 2 ZTs from most locations identified for coverage. By placing ZTs
in closer proximity to each other than normal spacing, access to more ZTs in any one spot is supported.
In any one zone (an area covered by one ZT, but potentially equipped with more), up to 36 simultaneous
calls can be supported within the given 10MHz of the U-PCS band.
ƒ Each Zone Transceiver provides for up to three simultaneous connections to D term PS III users within the
covered area. As users communicating through a ZT move out of its range and into an area covered by
another ZT, the connection is automatically switched (called a handover) to the new ZT (noticeable by a
momentary disruption in talk path (Note)). With the proper placement of ZTs throughout the facility, users
can move about the area while communicating (or idle) and have their calls follow them
.
ƒ The ZT is supplied with mounting hardware and can be installed on walls, mounted on solid ceilings or
placed above drop ceilings. The Zone Transceiver II is also offered with a weather resistant outdoor
enclosure, mountable on outside building walls or poles. Options for both fan cooled or heated
enclosures are also available.
ƒ NEC offers both ZT IIS and ZT IIU units and a combination of both. ZT IIU can be deployed using 1 pair
or 2 pair wiring. ZT IIS uses 2 pair wiring only.
Note: With ZTs version 7.2 or higher seamless handover can be achieved.